In desktop computing, it is now common to connect external peripherals such as mice, keyboards or display devices to a computing device such as a standard desktop computer, a laptop or even a mobile device such as a smartphone or tablet computer. A computing device which is supplying data to or controlling a peripheral is commonly known as a host. A host such as a standard desktop computer will, in general, be provided with specific output ports for each variety of output data. For example, it may have a single VGA port for video data. The connection of additional peripherals for which there are no specific ports is difficult, as it would generally require the user to install additional ports or internal devices such as additional hard drives or graphics cards. Solutions along these lines are relatively expensive and may be difficult for less-technical users.
An alternative method of connecting an external peripheral is to connect each peripheral to a USB socket on the host, as all modern computers are provided with multiple USB sockets. This provides a simple connection topology, but requires additional hardware and software to be present, as in general, USB has a low bandwidth that makes the provision of good-quality video output or fast data transfer, for example, a non-trivial task.
A USB cable commonly comprises one or more pairs of signal links, a pair being known as a data channel, where one of the links carries data in one direction and the other link carries data in the other direction, i.e. there is an upstream and a downstream link for each channel. The USB cable, when connected to a USB connector at each end, forms part of a USB connection, together with a USB controller at each of the devices at each end of the USB cable. Nevertheless, if data only needs to be transmitted primarily in one direction, for example where the connection is from a user input device such as a microphone, there will be no data input to the microphone and therefore only half of the USB connection's limited bandwidth will be in use. This results in wasted resources.
The invention seeks to address at least part of the above-described problem.